/*
 * Copyright (C) 2005 Luca Veltri - University of Parma - Italy
 *
 * This file is part of MjSip (http://www.mjsip.org)
 *
 * MjSip is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * MjSip is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with MjSip; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Author(s):
 * Luca Veltri (luca.veltri@unipr.it)
 */

package org.zoolu.net;


//import java.net.InetAddress;
import java.io.*;


/** TcpConnection provides a TCP connection oriented transport service.
 */
public class TcpConnection extends Thread
{
    /** The reading buffer size */
    static final int BUFFER_SIZE=65535;

    /** Default value for the maximum time that the tcp connection can remain active after been halted (in milliseconds) */
    public static final int DEFAULT_SOCKET_TIMEOUT=2000; // 2sec

    /** The TCP socket */
    TcpSocket socket;

    /** Maximum time that the connection can remain active after been halted (in milliseconds) */
    int socket_timeout;

    /** Maximum time that the connection remains active without receiving data (in milliseconds) */
    long alive_time;

    /** The InputStream */
    InputStream istream;

    /** The OutputStream */
    OutputStream ostream;

    /** InputStream/OutputStream error */
    Exception error;

    /** Whether it has been halted */
    boolean stop;

    /** Whether it is running */
    boolean is_running;

    /** TcpConnection listener */
    TcpConnectionListener listener;


    /** Costructs a new TcpConnection */
    public TcpConnection(TcpSocket socket, TcpConnectionListener listener)
    {  init(socket,0,listener);
        start();
    }


    /** Costructs a new TcpConnection */
    public TcpConnection(TcpSocket socket, long alive_time, TcpConnectionListener listener)
    {  init(socket,alive_time,listener);
        start();
    }


    /** Inits the TcpConnection */
    private void init(TcpSocket socket, long alive_time, TcpConnectionListener listener)
    {  this.listener=listener;
        this.socket=socket;
        this.socket_timeout=DEFAULT_SOCKET_TIMEOUT;
        this.alive_time=alive_time;
        this.stop=false;
        this.is_running=true;

        this.istream=null;
        this.ostream=null;
        this.error=null;
        try
        {  istream=new BufferedInputStream(socket.getInputStream());
            ostream=new BufferedOutputStream(socket.getOutputStream());
        }
        catch (Exception e)
        {  error=e;
        }
    }


    /** Whether the service is running */
    public boolean isRunning()
    {  return is_running;
    }


    /** Gets the TcpSocket */
    public TcpSocket getSocket()
    {  return socket;
    }


    /** Gets the remote IP address */
    public IpAddress getRemoteAddress()
    {  return socket.getAddress();
    }


    /** Gets the remote port */
    public int getRemotePort()
    {  return socket.getPort();
    }


    /** Stops running */
    public void halt()
    {  stop=true;
    }


    /** Sends data */
    public void send(byte[] buff, int offset, int len)  throws IOException
    {  if (!stop && ostream!=null)
    {  ostream.write(buff,offset,len);
        ostream.flush();
    }
    }


    /** Sends data */
    public void send(byte[] buff)  throws IOException
    {  send(buff,0,buff.length);
    }


    /** Runs the tcp receiver */
    public void run()
    {
        byte[] buff=new byte[BUFFER_SIZE];
        long expire=0;
        if (alive_time>0) expire=System.currentTimeMillis()+alive_time;
        try
        {  if (error!=null) throw error;
            socket.setSoTimeout(socket_timeout);
            // loop
            while(!stop)
            {  int len=0;
                if (istream!=null)
                {  try
                {  len=istream.read(buff);
                }
                catch (InterruptedIOException ie)
                {  if (alive_time>0 && System.currentTimeMillis()>expire) halt();
                    continue;
                }
                }
                if (len<0)
                {  //error=new Exception("TCP connection closed");
                    stop=true;
                }
                else
                if (len>0)
                {  if (listener!=null) listener.onReceivedData(this,buff,len);
                    if (alive_time>0) expire=System.currentTimeMillis()+alive_time;
                }
            }
        }
        catch (Exception e)
        {  error=e;
            stop=true;
        }
        is_running=false;
        if (istream!=null) try {  istream.close();  } catch (Exception e) {}
        if (ostream!=null) try {  ostream.close();  } catch (Exception e) {}
        if (listener!=null) listener.onConnectionTerminated(this,error);
        listener=null;
    }


    /** Gets a String representation of the Object */
    public String toString()
    {  return "tcp:"+socket.getLocalAddress()+":"+socket.getLocalPort()+"<->"+socket.getAddress()+":"+socket.getPort();
    }

}
